Passivation of nitinol wire for vascular implants - A demonstration of the benefits

  • O'Brien B
  • Carroll W
  • Kelly M
  • 51


    Mendeley users who have this article in their library.
  • 114


    Citations of this article.


This study investigated a passivation process for polished nitinol wires and vascular stent components, after being given a typical shape setting heat treatment. Heat treated samples were passivated in a nitric acid solution and a series of corrosion tests, surface analysis and chemical analysis was performed. Potentiodynamic polarization tests demonstrated a significant increase in breakdown potential for passivated samples, compared to heat treated surfaces. Surface analysis indicated that the passivation reduces Ni and NiO content in the oxide and increases TiO2content. Chemical analysis of passivation solutions suggests that the improvement in corrosion resistance is proportional to the quantity of nickel removed. Long term immersion tests demonstrate that nickel release from the surface of the material decreases with time and the quantity of nickel released is lower for passivated samples. The improved corrosion resistance is maintained after extended periods of immersion in saline solution. © 2002 Elsevier Science Ltd. All rights reserved.

Author-supplied keywords

  • Corrosion
  • Implants
  • NiTi
  • Passivation

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text


  • B. O'Brien

  • W. M. Carroll

  • M. J. Kelly

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free